[Coco] CoCo 1 64K upgrade failed :(.
cyouse at serialtechnologies.com
Fri Sep 26 16:55:32 EDT 2008
On Fri, 2008-09-26 at 21:46 +0100, Phill Harvey-Smith wrote:
> My answer to that would have to be 'maybe' I have done this on a Dragon
> 32 board and it did seem to work ok, however it is out of spec as the
> 74LS783 SAM can only do 128 cycle refresh, where as the 41256 type chips
> need 256 cycle refresh however like I said I tried it and it did seem to
> work, so may be worth a shot.
Ah, but if you're only using the lower half, only the lower half needs a
refresh, no? :)
Talking out of my ass here, don't remember the innards of DRAMs anymore,
but I don't see the need to recharge the caps in the unused
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